Bus Interface Unit (BIU) and Execution Unit (EU) tutorial

 Question

The diagram above is the function block diagram for Intel 8088. What are the functions played by the Bus Interface Unit and Execution Unit? How both complement each other.

Answer

Both BIU and EU have their own job specification. BIU is the unit that will oversea data or operand transfer from its original source to EU. EU is the unit that handle operation execution be it arithmetic operation or logic operation.

By separating both function, both can run concurrently therefore would enable pipelining which would expediate microprocessor processing.